The ’Brug van het access Hoofdweg-Westzijde’ is a bridge on the Voorkanaal which is now a Unesco monument. The canals were built as part of a defence network after the 80 years war, although this bridge is more modern. The defensive lines were designed to flood certain areas of the country just enough that infantry could not travel easily, but not deep enough to allow the use of boats. The defence network is no longer in operation, but many of the buildings remain as national monuments.